Please advise me what is best to use to provide a "cover" for the throat.

Hi, for a month I constantly have a sore throat and burning tongue( it is red and on the back I have a white raid). A visit to the ENT showed only the insufficiency of the voice, the morphology is all right. I was referred for an examination of whether I was undergoing coronavirus, a negative result. The doctor told me to eat kisiel (I do not hide that after eating the ailments gently, but for a short while) and suck tablets that will provide a "cover" for the throat. In the pharmacy I was advised icelandic lichen, unfortunately I do not see improvement. I had an X-ray of my lungs in the description of the information that I have few adhesions of the diaphragm. The only thing I can add is that more than a month ago I had to pluck surgically eight and stopped birth control pills (I do not know if it has any connection but I'm looking for a cause already everywhere). Please help, yours.